What is CVE-2022-39028?

CVE-2022-39028 is a high-severity vulnerability in GNU Inetutils, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2022-08-30.

How severe is CVE-2022-39028?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2022-39028 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

NULL pointer dereference in GNU Inetutils

CVE-2022-39028

telnetd in GNU Inetutils through 2.3, MIT krb5-appl through 1.0.3, and derivative works has a NULL pointer dereference via 0xff 0xf7 or 0xff 0xf8. In a typical installation, the telnetd application would crash but the telnet service would remain available through inetd. However, if the telnetd application has many crashes within a short time interval, the telnet service would become unavailable after inetd logs a "telnet/tcp server failing (looping), service terminated" error. NOTE: MIT krb5-appl is not supported upstream but is shipped by a few Linux distributions. The affected code was removed from the supported MIT Kerberos 5 (aka krb5) product many years ago, at version 1.8.

Published 2022-08-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.021 (81.5th percentile), scored 2026-10-20.

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 81.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.021 · newest: 0.021 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

Public proof-of-concept exploits

sanjay-embedded/sanjay-embedded

References

lists.gnu.org/archive/html/bug-inetutils/2022-08/msg00002.html (Mailing List, Vendor Advisory)
pierrekim.github.io/blog/2022-08-24-2-byte-dos-freebsd-netbsd-telnetd-netkit-te… (Exploit, Patch, Third Party Advisory)
git.hadrons.org/cgit/debian/pkgs/inetutils.git/commit/ (Patch, Mailing List, Vendor Advisory)
lists.debian.org/debian-lts-announce/2022/11/msg00033.html (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2022-39028?: CVE-2022-39028 is a high-severity vulnerability in GNU Inetutils, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2022-08-30.
How severe is CVE-2022-39028?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2022-39028 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.